The package was taken from a communal store for a blocks of apartments on Cordier Hill some time between 12:44 and 14:00 on Thursday last week.
The parcel contained a black ICube 2, for Phonax Hearing Aids.
Anyone with information in relation to this theft or the whereabouts of this item is asked to contact Guernsey Police on 725111.
Alternatively, witnesses can contact CrimeStoppers anonymously on 0800 555 111.